Owner`s Manual - Two

K&M
INPUT
LTD
Two-Ro
Owner's Manual
Thank you for your purchase of a
K&M LTD
amplifier from
K&M Analog Designs, LLC.
As a discerning guitarist, you know the road to great
tone begins with great components.
Our classic design, carefully selected parts and hand-built
approach combine to make an extremely versatile instrument.
Please take the time to read this manual. We hope it will
answer any questions you may have.
We extend a warm welcome to you as a member of a select
group of musicians who have chosen a Two-Rock amplifier.
Page 1
FRONT PANEL FUNCTIONS
1
5
BRIGHT
6
7
8
13 14
LEAD
DEEP
EQ1
BYPASS
BASS
GAIN
17
18
LEAD
MID
EQ2
CLEAN
INPUT
TREBLE
MIDDLE
MASTER LEAD GAINL EAD MASTER REVERB PRESENCE
K&M
LTD
2
3
4
9
10
11
12
15
ON
STANDBY
16
1. INPUT JACK- High impedance input to the amplifier. Plug in your
instrument here.
2. TREBLE CONTROL- Adjusts the high-frequency response. In the full
counter-clockwise position, high frequencies are bypassed to ground. In the
full clockwise position, high frequencies are allowed to pass to the next gain
stage.
3. MIDDLE CONTROL- Adjusts the mid-range response. In the full counterclockwise position, the tone will be somewhat “scooped” of mid-range
response, emphasizing the highs and lows. In the full clockwise position,
mid-range frequencies are allowed to pass to the next gain stage.
4. BASS CONTROL- Adjusts the bass response. In the full counterclockwise
position, low frequencies are cut. In addition, the response of the treble and
mid-range controls is greatly reduced. In the full clockwise position, low
frequencies are allowed to pass to the next gain stage.
5. BRIGHT SWITCH- Boosts the high frequency response. This is most
effective when the input gain is set at 12 o’clock or lower. The effect is less
dramatic as the input gain control is adjusted past the 12 o’clock position.
6. MID SWITCH- The mid boost function is assignable to either the clean or lead
channel, or off. The center position is off. In the "DOWN" position, the mid
boost is engaged whenever the clean channel is selected. In the "UP"
position, the the mid boost function is engaged whenever the lead channel is
selected.
7. DEEP SWITCH- Boosts the low and low-mid frequencies. This is a low
frequency contour switch, changing the low and low-mid response.
Page 2
8. EQ1/EQ2- This switch allows you to choose between 2 completely
different equalization setting. EQ1 is a lower gain setting, with extended
midrange and bass available when used in conjunction with the middle and
bass controls as well as the deep switch. This setting is suitable for any style
requiring a pure clean tone with a nice round bottom and plenty of
headroom.
EQ2 is a higher gain setting , allowing a greater signal level to pass to the
lead channel. This setting is suitable for any style requiring a clean to
slightly distorted tone in clean mode , and more gain in the lead mode.
9. INPUT GAIN- Adjusts the overall gain of the amplifier. Start with this
control in the 12 o’clock position. Keep in mind that the amount of gain set
here determines the signal level feeding the lead channel. Low gain settings
of this control will require higher
lead gain
MIDDLE
BASS settings for the same amount of
TREBLE
MIDDLE
BASS
TREBLE
overdrive.
10. CLEAN CHANNEL MASTER VOLUME- Adjusts the output level of
the clean channel.
11.
LEAD GAIN- Adjusts the input level (gain) of the lead channel.
At lower settings, a slightly overdriven tone can be achieved.
As the control is adjusted clockwise, the overdrive effect increases.
12. LEAD MASTER- Adjusts the output level of the lead channel.
13. BYPASS SWITCH- This switch bypasses the tone controls, increasing both
level and mid-range response.To enable foot switch control of this function,
switch must be in the down position.
14. LEAD CHANNEL SWITCH- Sends the instrument signal through the lead
circuit, adding extra stages of gain to the signal and enabling the lead gain
and lead master controls. To enable foot switch control of this function,
switch must be in the down position.
15. REVERB- Mixes the dry signal with a high quality spring-type
reverberation effect. This effect is defeated with the control in the full
counterclockwise position.
16. PRESENCE CONTROL- Adjusts the contour of high-frequency
response. The high frequency response will increase as you advance the
control clockwise.
17. STAND-BY SWITCH- The LTD is equipped with a three position STANDBY
switch. In the center position, the amp is in STANDBY mode. In the "DOWN"
position, the amp is operating with a low plate voltage setting. This is
considered the LOW POWER mode. In the "UP" position, a higher plate
voltage is supplied, and this is considered HIGH POWER mode. The difference
in power between the 2 modes is approximately 25%, depending on tubes
and class of operation.
Page 3
18. INDICATOR LAMP- This lamp will illuminate when the power switch is in
the “up” position, indicating the unit is receiving A/C power.
NOTE: All switches are ON in the “up” position.
Two-Rock, CA
REAR PANEL FUNCTIONS
2
1
A/C 120/220/240 VOLTS
50 / 60 CYCLES
3
4
FUSE POWER
CllassA
2.5 AMP
SLO-BLO
ClassA/B
5
11
FOOTSWITCH SPEAKER OUTPUTS
EFFECTS LOOP
LOOP
BYPASS SEND RETURN LEVEL
LEAD EQ
TREBLE MIDDLE
Manufactured by:
4 OHM 8OHM 16 OHM
K&M Analog Designs
S/N
6
BASS
7
8
9
MAD E IN U.S.A.
Two-Rock, CA
10
1. A/C INPUT- Connects the amplifier to A/C power via the power cord
supplied. Unless otherwise specified, your amplifier is designed to operate
on 120 volts A/C, 60 cycles.
2. FUSE- 3 AG Type, slow blow fuse. Refer to the legend below the fuse holder
for the proper fuse rating for your amplifier. (50 watt-2.5 amp /100 watt3.5 amp)
3. POWER SWITCH- Turns the power on.
4. CLASS A-A/B SWITCH- This function switch changes the POWER SECTION
from CLASS A to CLASS A/B mode.
CAUTION! You must reset the bias current when you change output tubes
for Class A/B operation! In cathode bias mode(class A), you may insert any
matched pair of 6L6, EL34, 6V6, or 5881 without rebiasing in the amp. You
may also operate the amp in high or low power mode. In class A/B, be sure
the tubes used are matched, and the correct bias current is used.
FAILURE TO DO SO MAY DAMAGE THE TUBES, THE AMPLIFIER, OR
BOTH!
5
FOOTSWITCH JACK- Connect the foot switch assembly here to enable
remote switching of the lead/rhythm and bypass functions
6. SPEAKER OUTPUT JACKS- There are 3 speaker output jacks- 4,8 and 16 ohm.
NEVER OPERATE YOUR AMPLIFIER WITHOUT A PROPER SPEAKER
LOAD CONNECTED. Be sure to match the impedance of your cabinet with
the impedance (output) of the amplifier.
Page 4
7. LOOP BYPASS SWITCH- The EFFECTS LOOP can be bypassed by placing the
LOOP BYPASS SWITCH in the "UP" position. The overall gain of the amp will
be significantly reduced, and the effects level control becomes a reverb
drive control.
8. EFFECTS SEND- Use this jack to send the amplifiers signal to
outboard effects.
9. EFFECTS RETURN- Use this jack to connect the output of your
effects to the amplifier.
10.
EFFECTS LEVEL- Adjusts the return signal level. It also acts as a master
volume control. Do not set fully counterclockwise, as this will shut off signal
to the output section, resulting in no output level. Normally this control
should be set at the 12 o’clock position.
11. LEAD EQ - The TREBLE, MIDDLE, and BASS controls on the rear panel affect
only the LEAD CHANNEL.
NOTE: Both the “Lead” and “Bypass” front panel switches must be
in the “down” position to enable footswitch function.
Page 5
FOOT SWITCH
Lead
(Blue LED)
Bypass
(Red LED)
TUBE COMPLEMENT
The Tube Location
V1- 12AX7, Lead channel
V2- 12AX7, Clean channel
Front
V3- 5751/12AT7, Reverb driver
V3 V1
V4- 12AX7, Reverb / effects
V5- 12AX7, Phase inverter
V6, V7- Output
V7 V6
V5 V4 V2
Rear
Each fine production tube is tested and matched to our exacting specifications.
External bias adjustment and test points are located on the chassis near the
output tube sockets.
A digital voltmeter and small screwdriver are required for bias adjustment.
BIAS ADJUSTMENT-Power up unit. Connect proper speaker load. Set master
volumes and effects return controls to zero.
Do not apply any signal to the input during the biasing procedure!
Take unit off STANDBY. Allow a few seconds for the circuit to stabilize.
Set meter to millivolt scale.( Or lowest volt scale.60 millivolts = .060 volts.) With
meter grounded to chassis and + probe at test point, measure voltage. A reading
of .055 to .060 volts is normal. If not in this range,adjust by turning bias screw
Page 6
SLOWLY a small amount. Do not set above .070!
For other tube types(5881, 6550, EL34) check with manufacturer or contact us
for recommendations.
Settings higher than .065 with 6L6 tubes may cause premature tube wear and
possibly damage the amplifier. Keep in mind that tubes vary in quality, and
some tubes can handle upwards of 40 ma each ( a reading at the test point of
.080 !) However, to be on the safe side, use the above as a guide.
WARNING! No user serviceable parts inside! Refer service to qualified service
person only.
LINE CORD- For your safety, connect to grounded A/C receptacle only.
Page 7
K&M Analog Designs
amplifiers are brought to
you by Bill Krinard and Joe Mloganoski. We know your new
K&M LTD
amplifier will provide many hours of enjoyment and
inspiration in the years to come.
This manual is a resource for some of your questions.
Please contact us with any other questions or comments
you may have. We look forward to hearing from you!
PHONE:
1.707.584.TONE (8663) (M-F 9am – 5pm PST)
FAX:
1.707.584.8661
MAILING ADDRESS:
K&M Analog Designs, LLC
619 Martin Avenue, Suite 6
Rohnert Park, CA 94928
E-MAIL:
Joe Mloganoski, Product Specialist
Joe@Two-Rock.com
Bill Krinard, Chief Engineer
Bill@Two-Rock.com
INTERNET:
www.two-rock.com
PRECAUTIONS:
Do not expose to rain or any other moisture
Do not use cleaning solvents. Wipe exterior with a clean,
dry cloth only.
Refer servicing to a qualified service technician.
Page 8
This is a product of
K & M Analog Designs, LLC
619 Martin Avenue, Suite 6
Rohnert Park, CA 94928
Serial Number:___________